Bluetooth: availabilitychanged event

Secure context: This feature is available only in secure contexts (HTTPS), in some or all supporting browsers.

Experimental: This is an experimental technology
Check the Browser compatibility table carefully before using this in production.

The availabilitychanged event fires when the Bluetooth system as a whole becomes available or unavailable to the User Agent.


Use the event name in methods like addEventListener(), or set an event handler property.


addEventListener("availabilitychanged", (event) => { })

onavailabilitychanged = (event) => { }

Event type

A generic Event.


To be informed when Bluetooth availability changes, you can add a handler to your Bluetooth instance using addEventListener(), like this:


Bluetooth.addEventListener("availabilitychanged", (event) => {
  const availability = event.value;

Alternatively, you can use the Bluetooth.onavailabilitychanged event handler property to establish a handler for the availabilitychanged event:


Bluetooth.onavailabilitychanged = (event) => {
  const availability = event.value;


Web Bluetooth
# eventdef-bluetooth-availabilitychanged
Web Bluetooth
# dom-bluetooth-onavailabilitychanged

Browser compatibility

BCD tables only load in the browser

See also